whats a surge protector ?? and when the lights go out.. which they do in rainy season isnt it a huge risk for the psu ?
Surge protectors protect against voltage spikes caused by environmental anomalies such as lightning strikes and transformer explosions. Most power bars have surge protectors built in and many PSUs also have surge protectors.
All UPS' also have surge protectors by design.
There's no risk to the PSU when there's a sudden loss of power, all you'll lose is any unsaved data. However, power loss can sometimes be preceded by a sudden drop in transmission line voltage (brownout) which is a safety measure to protect the electrical grid. Brownouts can do all sorts of nasty things to electrical devices including cheap power supplies. Most decent power supplies are equipped to handle brownouts and small voltage spikes but it never hurts to put another surge protector in the middle.